Hand held vacuums which utilize a fluid, such as a liquid cleaning fluid or steam, to enhance cleaning are known. Operation of such vacuums is typically carried out via at least two separate and independent switches: a heater switch and a main function switch. The heater switch may be a rocker type switch for controlling the heater. The heater switch has two switch positions, heater “On” and heater “Off.” The main function switch is a four position slider switch having four different switch positions: “Spray,” “Steam,” “Off,” and “Vacuum.” When the function switch is at the “Vacuum” position, only the vacuum motor operates. When the function switch is at the “Steam” position, the water pump operates at a low speed. When the function switch is at the “Spray” position, the water pump operates at a high speed. When the function switch is at the “Off” position, the vacuum motor and water pump are deactivated.
Operation of a hand held vacuum using the two switch configuration described above is extremely cumbersome and may result in damage to the item being cleaned. For example, if the user fails to switch the heater to the “On” position before actuating the main function switch to either the “Steam” position or the “Spray” position, the vacuum will discharge cold water onto the item being cleaned, thereby possibly causing damage to the item.
In addition, the two switch configuration may lead to other problems. Due to the independent operation of the two switches, it is conceivable that the heater may be inadvertently left on. For instance, the operator may slide the main function switch to the “Off” position, and yet fail to turn off the heater. Leaving the heater on for a prolonged period of time may damage the heater and possibly shorten the life of the heater and components of the vacuum associated with the heater. Consequently, a need exists in the art to develop a hand held steam vacuum that eliminates the possibility of producing a cold water spray when steam is desired and only allows the heater to be energized when used in the “Steam” and “Spray” modes of operation.